The present disclosure relates to regulating a printing device or machine having multiple Integrated Marking Engines (IMEs). It finds particular application in conjunction with xerographic devices or machines, and will be described with particular reference thereto. However, one of ordinary skill in the art will appreciate that it is also amenable to other like applications.
Printing devices are known to include multiple IMEs. For example, printing devices are known which include two or more IMEs. Typically, before such printing devices begin printing, each IME therein is warmed-up. The IME warm-up commonly occurs during the initial powering-up or turning-on of the printing device, or when the printing device is awoken from a sleep, power saver or other like power conservation mode. IME warm-up generally includes supplying electrical power to the IME for a period of time, e.g., to bring a fuser and/or other components of the IME from a lower ambient temperature up to a target operating temperature or otherwise prepare the IME for operation. Once the warm-up is completed, the power supplied to the IME can be typically reduced from a warm-up level to a lower operating level.
Generally speaking, there are typically several levels of power consumption in a machine that depend on the mode or state of operation of the machine at the moment. These modes include (1) off wherein no power is being consumed, (2) power saver is a dormant state wherein very low power is being consumed for vital functions such as monitoring for incoming print or fax jobs, (3) warm-up wherein a relatively large amount of power is being consumed to bring the machine from off or power saver to the ready states, (4) standby wherein the machine is ready but not running a job and (5) run wherein the machine is ready and running a job. In order to conserve energy, the machine is typically programmed to go from run to standby whenever there are no more jobs in the queue to be printed and then to go from standby to power saver after a period of inactivity.
Conventionally, all the components (including the IMEs) within an integrated printing device are warmed-up simultaneously even though the power required for warm-up may be greater than the power required to run the device after warm-up. Accordingly, the total power available to the device for warm-up is divided among all of the components in the device. When the device contains multiple integrated IMEs, the power service to the device, or the limitations of the power supplies within the device, may limit the power available for warm-up when the IMEs all warm-up simultaneously. Depending on various factors, e.g., the thermal mass of the individual fusers and the total available power for IME warm-up, the warm-up time for the printing device can be undesirably long. Moreover, the simultaneous warm-up of multiple IMEs within a printing device can negatively impact a first-page-out-time (FPOT) of the printing device, i.e., the time it takes for the printing device in a given instance to provide or output the first copied or printed page of an input job. Generally, a long FPOT can result in dissatisfaction to the user.
A recent improvement for limiting or reducing the FPOT in a multiple IME device has been described as sequential warm-up of IMEs. Sequential warm-up provides for the maintenance of power consumption within acceptable limits, yet minimizes the impact on warm-up time. However, all the IMEs within the printing device may be typically warmed-up in the same sequential order (i.e. IME-1 warmed-up first, IME-2 warmed-up second, IME-3 warmed-up third, etc.). The same pattern of usage and/or powering up of the individual IMEs can result in uneven utilization of certain IMEs and uneven use of consumables consumption or customer replaceable units (CRU) as the IMEs typically begin printing as soon as they are warmed up. Alternatively, the sequential warming-up or powering-up IMEs may be done simultaneously or at random without regard to the duration of processing the immediate jobs relative to the duration required to power-up one or more additional IMEs. In either case, the FPOT may be longer than necessary and the use of power may be greater than necessary for situations where the jobs are short run and are spaced out over time.
Accordingly, a new and improved multiple IME printing device and/or method for warming-up multiple IMEs within a printing device are disclosed that overcome the above-referenced problems and others.